As a linear slide apparatus of this kind which straightly drives a table handling a workpiece by means of an electromagnetic actuator, apparatuses having various structures are conventionally proposed. For example, according to a linear slider described in Japanese Patent Application Laid-open No. 2002-96233, a guide rail is mounted on an upper surface of a plate-like fixed stage, a moving element comprising an armature core and an armature coil is slidably supported on the guide rail through a slider, and a table is mounted on an upper surface of the moving element. Plate-like magnetic field yokes rise from both side ends of the fixed stage to surround the moving element from both sides, permanent magnets are mounted on the magnetic field yokes to form a stator, and the stator and the moving element constitute a linear motor. The moving element is moved along the guide rail by means of thrust generated when the armature coil is energized.
According to such a conventional linear slider, however, since the table is directly mounted on the upper surface of the moving element which has the armature coil, heat from the coil is directly transferred to the table, the heat is transferred to a workpiece on the table, and the temperature of the workpiece is prone to be increased. When the linear slider is used in semiconductor production equipment, it is necessary to prevent heat from being transferred to a semiconductor as much as possible.
Japanese Patent Application Laid-open No. 2001-352744 discloses a technique in which an armature assembly having an exciting coil is provided on the side of a bed instead of on the side of the table. According to this document, the above-described problem of heat transmission can be solved. However, since the table is slidably supported by two parallel guide rails, the structure is complicated, and it is troublesome to match axes of the two guide rails with an axis of an electromagnetically driving portion.